The invention described herein may be manufactured and used by and for the Government of the United States of America for Governmental purposes without the payment of any royalties thereon or therefor.
Not applicable.
(1) Field of the Invention
The invention relates to missile launch assemblies and is directed more particularly to an elastomeric powered assembly for launching missiles, such as torpedoes.
(2) Description of the Prior Art
High impulse, short duration fluid pumps are known in the art and are used in submarine torpedo launch systems. Usually, such pump systems require high power piston or turbine machinery to provide the required high velocity fluid flow in a very short time. An attractive alternative to high-powered machines are relatively simple elastic bulbs which expand to contain a volume of fluid, such as sea water, under pressure. Upon release of the water, the bulb quickly returns to its non-expanded state, propelling the water at a high velocity into and through a torpedo tube to effect launch of a torpedo, or other missile, therein.
Elastomeric expandable impulse energy storage and transfer systems are shown and described in U.S. Pat. Nos. 4,848,210, issued Jul. 18, 1989, in the name of Laurent C. Bissonnette, and 5,200,572, issued Apr. 6, 1993 in the names of Laurent C. Bissonnette et al.
In the ""210 patent there is disclosed a bladder device for storing potential energy when distended and rapidly converting that stored energy into kinetic energy of a working fluid, for quietly ejecting a projectile from a launch system into a surrounding fluid medium. In the ""572 patent there is disclosed an elastomeric impulse energy storage and transfer system including an accumulator body of elastomeric material, the body having an opening at a base portion thereof, and having in elevation an ellipsoidal configuration. The body receives and discharges fluid through the opening and is expandable and contractible in response to receiving and discharging, respectively, the fluid. The body retains the ellipsoidal configuration when in an expanded condition. A submarine projectile launch system includes the accumulator body as a component thereof.
An innate difficulty in structuring such pump and storage devices is in the provision of an elastomeric bulb adapted to contain a large volume of relatively incompressible liquid at pressure sufficiently high to propel the liquid at a high velocity.
Typically, when a disc is used in such a system, a very large rubber disk is mounted in a free flood area of a submarine in such a configuration that one side of the rubber disk is open to sea while the other side is ported to breech ends of the submarine""s torpedo tubes. When water is pumped between the disk and torpedo tube, the rubber disk inflates. Water continues to be pumped in this area until the displacement of the disk is approximately equal to the volume of a missile, or other device, in the torpedo tube. When a valve is opened at the breech end of the tube, the pressurized water ejects the device out of the tube while the elastomer returns to its unstretched configuration. This type of system is very effective in effecting a quiet launch, as the only noise associated with the launch are vibrations initiated by the ejection water traveling through the launch system. However, the volume of water required to effect this type launch is quite large as the shot of water must approximate the volume of the device being launched. The volume requirement can require that the underwater vehicle be larger than desired. This, in turn, results in a substantial cost increase.
Accordingly, there is a need for an expandable energy storage device and fluid pump which provides reliability and durability, which operates quietly, and which provides the required volume of fluid but with a relatively small elastomeric, energy-storing member.
An object of the invention is, therefore, to provide an expandable pump and energy storage device which is reliable and durable, which operates quietly, and which, though of limited size, provides the necessary volume of fluid to propel a missile of torpedo size from a launch tube.
With the above and other objects in view, as will hereinafter appear, a feature of the present invention is the provision of a launch assembly for underwater vehicles, the assembly comprising a launch tank having mounted therein is an expandable elastomeric disc and a turbine. The assembly further includes a water inlet conduit, an impulse tank interconnecting the water inlet conduit and a missile launch tube, and a pump inducer mounted in the water inlet conduit and drivable by the turbine. Movement of the disc from an expanded to a non-expanded condition causes water in the launch tank to drive the turbine to drive the pump inducer to pump water from the water inlet conduit to the impulse tank and thence to the launch tube to effect launch of a missile therein.
The above and other features of the invention, including various novel details of construction and combinations of parts, will now be more particularly described with reference to the accompanying drawings and pointed out in the claims. It will be understood that the particular assembly embodying the invention is shown by way of illustration only and not as a limitation of the invention. The principles and features of this invention may be employed in various and numerous embodiments without departing from the scope of the invention.